On Mon, 12 Jul 2010 12:48:30 -0700 (PDT), Joe wrote:

On Jul 12, 2:33*pm, harry wrote:
On Jul 12, 8:24*pm, "Nonny" wrote:





Harbor Freight sells one of those "tools you put in your toolbox
and only get out rarely when all else has failed." *It's called an
impact screwdriver. *They've been around forever, and the one I
just got cost less than what I paid for one 55 years ago.

What they are is a very heavy solid steel handle with a coarse
pitched screw thread inside, so to speak. *Inside the threaded
area is a mated shaft with reversing toggle, and on the end of the
shaft is a hex holder for various screwdriver bits. *The tool is a
heavy duty version of the Yankee drill we all remember. *They have
a socket wrench-type of shaft and apparently can also be used on
bolts, but I've never tried that, since I have a pneumatic wrench
that works well. *Their best application is in loosening frozen
screws, where an inward application of force and twisting motion
is needed.

To use the impact screwdriver, you place the appropriate bit in
the holder and hold the screwdriver firmly while tapping on it
with a hammer. *The impact forces the bit into the screw, helping
to prevent the head from stripping, while the coarse threads make
the bit twist just a tad. *Usually, that's enough to break loose a
frozen screw if you're lucky, and you then follow up with a
regular screwdriver to finish the job.

The first one I had I bought as a teen to work on my motorcycle's
engine and had it for around 40 years. *During that 40 years, I
probably had to use it a dozen times at the most. *However, each
and every time it saved the day for me. *The one Harbor Freight
sells appears to be a clone of my old one and I suspect it'll
serve the purpose longer than I'll ever need.

Nonny

I find they usually break the stud/bolt off.....................Or if
it's in screwdriver mode chew the head up.

Sounds like you have it confused with some other tool, an air impact
tool, maybe?

Yeah, I think he has. The difference between impact driver and
impact wrench, easy to miss perhaps, since drivers come with a square
shaftt that take sockets like from socket wrenches (although they
should be special "impact sockets".)

It's the very advantage of an impact driver that the momemnt of
twisting is the same moment that the driver is pressed hardest against
the work service. When any other screwdriver might lift up and
scrape off the top of a screw, the impact driver has lost all torque
by the time it can lift up.

There are better quality I'm sure, but JCWhitneys are pretty good and
they also sell a set of extra tips.

Two or three years ago, they had two models of impact driver, the
simple one I bought 30 years ago also, and one with a long handle and
a rubber donut guard to protect your hand from the hammer. I bought
them both and like the one with the guard.

Also Harbor Friegght has a small one, which I haven't used yet.

OTOH, Lowes and Home Depot had nothing like any of these. A strange
omission afaict.

When I was tryhing to get the covers off, the bolts out of, a
40-year-old motorcycle, this driver was essential. I messed up the
one bolt I worked on before I bought my new drivers. (I also had to
heat not the heads but the places where they screwed in with a propane
torch.

Had one in my tool box since the 1960's and it was the only thing that
would disassemble the early Honda motorbikes for repair. Worked well

Ah, you too!

with the retaining screw on many of the import cars brake discs and
drums. We learned to apply Kroil liberally before exceeding the yield
point of the fastener.
Possibly the most under-rated but useful tool around.

Joe